Zhang Run, Wang Suwei, Tian Jing, Chen Ke, Xue Ping, Wu Yihui, Chou Weimin
College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Polymers (Basel). 2020 Feb 21;12(2):483. doi: 10.3390/polym12020483.
Modified ultra-high-molecular-weight polyethylene (UHMWPE) with calcium stearate (CS) and polyethylene wax (PEW) is a feasible method to improve the fluidity of materials because of the tense entanglement network formed by the extremely long molecular chains of UHMWPE, and a modified UHMWPE sheet was fabricated by compression molding technology. A Fourier-transform infrared spectroscopy test found that a new chemical bond was generated at 1097 cm in the materials. Besides, further tests on the thermal, thermomechanical, mechanical, and shape memory properties of the samples were also conducted, which indicates that all properties are affected by the dimension and distribution of crystal regions. Moreover, the experimental results indicate that the addition of PEW and CS can effectively improve the mechanical properties. Additionally, the best comprehensive performance of the samples was obtained at the PEW content of 5 wt % and the CS content of 1 wt %. In addition, the effect of temperature on the shape memory properties of the samples was investigated, and the results indicate that the shape fixity ratio (R) and the shape recovery ratio (R) can reach 100% at 115 °C and 79% at 100 °C, respectively, which can contribute to the development of UHMWPE-based shape memory polymers.
用硬脂酸钙（CS）和聚乙烯蜡（PEW）改性超高分子量聚乙烯（UHMWPE）是一种可行的改善材料流动性的方法，这是因为UHMWPE极长的分子链形成了紧密的缠结网络，并且通过压缩成型技术制备了改性UHMWPE片材。傅里叶变换红外光谱测试发现材料在1097 cm处产生了新的化学键。此外，还对样品的热性能、热机械性能、机械性能和形状记忆性能进行了进一步测试，结果表明所有性能均受晶体区域尺寸和分布的影响。而且，实验结果表明添加PEW和CS可以有效改善机械性能。此外，在PEW含量为5 wt%和CS含量为1 wt%时，样品获得了最佳综合性能。另外，研究了温度对样品形状记忆性能的影响，结果表明形状固定率（Rf）和形状回复率（Rr）分别在115℃时可达100%，在100℃时可达79%，这有助于基于UHMWPE的形状记忆聚合物的发展。
